ФАЗОВЫЕ РАВНОВЕСИЯ В СИСТЕМАХ Cs2MoO4–R2(MoO4)3–Hf(MoO4)2 (R = Al, Cr, Fe, Bi, La–Lu)

Abstract

X-ray diffraction and differential scanning calorimetry methods are used to systematically study phase formation in the ternary salt systems Cs 2 MoO 4 -R 2 (MoO 4 ) 3 -Hf(MoO 4 ) 2 (R-trivalent elements In systems, the formation of new triple molybdates of the compositions Cs 5 RHf(MoO 4 ) 6 (R = Al, Cr, Fe, Bi) (S 1 ), Cs(RHf 0,5 )(MoO 4 ) 3 ,(R = Al, Fe, Cr) (S 2 ), Cs 2 RBiHf 2 (MoO 4 ) 6,5 (S 3 ) was detected. Taking into account the formation of new triple molybdates and the peculiarities of phase formation in facet systems, systems were triangulated in the subsolidus region. The thermal and electrophysical properties of synthesized compounds are determined. The triple molybdates Cs 5 RHf(MoO 4 ) 6 (R = Al, Cr, Fe) are isostructural to the compound Rb 5 FeHf(MoO 4 ) 6 (hexagonal symmetry, sp. gr. R`3,, Z = 2), the isoformed bismuth analogue crystallizes in the trigonal system (Pr. R3 = 3, Z = 6). The structural analog of Cs(RHf 0.5 )(MoO 4 ) 3 (R = Al, Cr, Fe) is Cs(FeZr 0.5 )(MoO 4 ) 3 (trigonal system, sp. gr. R3, Z = 6). The identification of diffractograms and the determination of the crystallographic characteristics of the new molybdates of the lanthanide series Cs 2 RHf 2 (MoO 4 ) 6.5 (R = Al, Cr, Fe, Bi, La-Lu) were carried out using the autoindication method with the TOPAS 4.2 software package.